1. Field of the Invention
This invention relates generally to semiconductor products, and, more particularly, to a method and apparatus for controlling semiconductor manufacturing processes to remove photoresist plasma.
2. Description of the Related Art
The technology explosion in the manufacturing industry has resulted in many new and innovative manufacturing processes. Today""s manufacturing processes, particularly semiconductor manufacturing processes, call for a large number of important steps. These process steps are usually vital, and, therefore, require a number of inputs that are generally fine-tuned to maintain proper manufacturing control.
The manufacture of semiconductor devices requires a number of discrete process steps to create a packaged semiconductor device from raw semiconductor material. The various processes, from the initial growth of the semiconductor material, the slicing of the semiconductor crystal into individual wafers, the fabrication stages (etching, doping, ion implanting, or the like), to the packaging and final testing of the completed device, are so different from one another and specialized that the processes may be performed in different manufacturing locations that contain different control schemes.
Among the important aspects in semiconductor device manufacturing are rapid thermal anneal (RTA) control, chemical mechanical polishing (CMP) control, etching, and overlay control.
The results from the analysis of the process errors are used to make updates to process tool settings manually. Generally, a manufacturing model is employed to control the manufacturing processes. Some of the problems associated with the current methods include the fact that the process tool settings are only updated a few times a month. Furthermore, currently the process tool updates are generally performed manually. Many times, errors in semiconductor manufacturing are not organized and reported to quality control personnel. Often, the manufacturing models themselves incur bias errors that could compromise manufacturing quality.
Generally, a set of processing steps is performed on a lot of wafers on a semiconductor manufacturing tool called an exposure tool or a stepper, followed by processing of the semiconductor wafers in etch tools. The manufacturing tool communicates with a manufacturing framework or a network of processing modules. The manufacturing tool is generally connected to an equipment interface. The equipment interface is connected to a machine interface to which the stepper is connected, thereby facilitating communications between the stepper and the manufacturing framework. The machine interface can generally be part of an advanced process control (APC) system. The APC system initiates a control script based upon a manufacturing model, which can be a software program that automatically retrieves the data needed to execute a manufacturing process. Often, semiconductor devices are staged through multiple manufacturing tools for multiple processes, generating data relating to the quality of the processed semiconductor devices. Many times, errors can occur during the processing of semiconductor devices. There are many manufacturing side effects that can affect the quality and efficiency of processed semiconductor wafers. These manufacturing side effects include plasma-induced electrical charges that can damage semiconductor devices being manufactured.
The present invention is directed to overcoming, or at least reducing the effects of, one or more of the problems set forth above.
In one aspect of the present invention, a method is provided for controlling plasma photoresist removal processes. At least one manufacturing run of semiconductor devices is processed. Environmental data is acquired in response to processing the semiconductor devices. Metrology data is acquired in response to processing the semiconductor devices. The method further comprises performing residual gas analysis based upon the acquired environmental data and the acquired metrology data.
In another aspect of the present invention, an apparatus is provided for controlling plasma photoresist removal processes. The apparatus of the present invention comprises: a processing chamber; a residual gas analyzer coupled with the processing chamber, the residual gas analyzer capable of detecting at least one type of residual gas in the processing chamber; and a processing tool controller coupled with the processing chamber and the residual gas analyzer, the processing tool controller being capable of terminating an operation of the processing chamber in response to a signal from the residual gas analyzer.